The invention concerns a device for punching printed cardboard, cardboard packagings, envelopes or similar subtates in accordance with the independent claim.
Conventional devices for processing printed substrates (U.S. Pat. No. 4,604,083) are formed as an integral part of a printing machine for processing sheets, wherein a printed substrate to be punched is inserted, via sliding elements, between rotating rollers and is processed by punching tool parts located on the roller peripheral surface. A register-controlled superposition of the printing with the finishing step is very difficult from a technical point of view and the processing accuracy is adversely affected.
The invention addresses the problem of creating a device for punching printed material, in particular packaging means or similar substrates, which can be used as an additional construction unit for almost any printing machine, which improves the processing accuracy in sheet printing through precise positional transfer of the substrate, and which can be rapidly adjusted to changed processing shapes as well as different substrates.
The invention achieves this object with a device having the features characterizing the independent claim. Further substantial design features are given in the dependent claims.
The inventive device for punching previously printed substrates has two conventional processing rollers, at least one of which has a gripper proximate its peripheral tool part to grasp the printed sheet, which is to be transported as a substrate, in a register-controlled fashion and introduce same into a register-controlled transport position between the processing rollers.
The rotating processing rollers and integrated gripper form a functional unit and the device therefore permits punching of the substrate during the same production sequence in which printing occurs. The range of applications of the device can also be augmented by embossing and/or perforation procedures. The substrate can be directly processed by a printing machine disposed upstream of the device in such a manner that this printing machine and the finishing device can be operated synchronously at high speed. The printed image and processing shape of the subsequent tool parts are thereby superposed in a register-controlled fashion and with improved accuracy. Different substrates can be processed with changed processing shapes after short retooling times such that the overall productivity of the processing sequence is increased by combining processing procedures.